<template>
  <div class="com-container">
    
    <div class="com-chart" ref="rank_ref">
      
    </div>
  </div>
</template>

<script>
import {mapState} from 'vuex'
export default {
  data () {
    return {
      chartInstance: null,
      allData: null, // 从服务器获取的所有数据
      startValue: 0, // 区域缩放的起点值
      endValue: 9,  // 区域缩放的终点值
      timeId: null, // 定时器的标识
    }
  },
  computed: {
    ...mapState(['theme']) 
  },
  watch:{
     theme() {
      console.log("主题切换了");
      this.chartInstance.dispose() // 销毁当前的图表
      this.initChart() // 重新以最新的主题名称初始化图表对象
      this.screenAdapter() // 完成屏幕适配
      this.updateChart() // 更新图表的展示
    }
  },
  created() {
    // 在组件创建完毕后, 注册回调函数
    this.$socket.registerCallBack("rankData", this.getData)
  },
  mounted() {
    this.initChart()
    // this.getData()
     this.$socket.send({
      action: 'getData',
      socketType: 'rankData',
      charName: 'rank',
      value: ''
    })
    window.addEventListener("resize", this.screenAdapter)
    this.screenAdapter()
  },
  destroyed() {
    window.removeEventListener("resize", this.screenAdapter)
    clearInterval(this.timeId)
    // 再组件销毁的时候,进行回调函数的取消
    this.$socket.unRegisterCallBack("rankData")
 },
  methods: {
    // 初始化方法
    initChart() {
      this.chartInstance = this.$echarts.init(this.$refs.rank_ref, this.theme)
      const initOption = {
        title: {
          text: '▎地区销售排行',
          left: 20,
          top: 20
        },
        grid: {
          top: '40%',
          left: '5%',
          right: '5%',
          bottom: '5%',
          containLabel: true
        },
        tooltip: {
          show: true
        },
        xAxis: {
          type: 'category'
        },
        yAxis: {
          type: 'value'
        },
        series: [
          {
            type: 'bar'
          }
        ]
      }
      this.chartInstance.setOption(initOption)
      this.chartInstance.on('mouseover', () => {
        clearInterval(this.timeId)
      })
      this.chartInstance.on('mouseout', () => {
        this.startInterval()
      })
    },
    // 获取服务器数据方法
    getData(ret) {
      // await this.$http.get()
      // 对allData进行赋值
      // const {data:ret} = await this.$http.get('rank')
      this.allData = ret
      this.allData.sort((a,b) => {
        return b.value - a.value // 从大到小进行排序
      })
      // console.log(this.allData);
      this.updateChart()
      this.startInterval()
    },
    // 更新图表
    updateChart() {
      const colorArr = [
        ['#0BA82C', '#4FF778'],
        ['#2E72BF', '#23E5E5'],
        ['#5052EE', '#AB6EE5']
      ]
      // 处理数据
      // 所有省份形成的数组
      const provinceArr = this.allData.map(item => {
        return item.name
      })
      // 所有省份对应的销售金额
      const valueArr = this.allData.map(item => {
        return item.value
      })
      const dataOption = {
        xAxis: {
          data: provinceArr
        },
        dataZoom: {
          show: false,
          startValue: this.startValue,
          endValue: this.endValue
        },
        series: [
          {
            data: valueArr,
            itemStyle: {
              color: (arg) => {
               let targetColorArr = null
               if(arg.value > 300) {
                 targetColorArr = colorArr[0]
               } else if(arg.value > 200)  {
                 targetColorArr = colorArr[1]
               } else {
                 targetColorArr = colorArr[2]                
               }
               return new this.$echarts.graphic.LinearGradient(0,0,0,1, [
                   {
                     offset: 0,
                     color: targetColorArr[0]
                   },
                   {
                     offset: 1,
                     color: targetColorArr[1]
                   }
                 ])
              }
            }
          }
        ]
      }
      this.chartInstance.setOption(dataOption)
    },
    screenAdapter() {
      const titleFontSize = this.$refs.rank_ref.offsetWidth / 100 *3.6
      const adapterOption = {
        title: {
          textStyle: {
            fontSize: titleFontSize
          }
        },
        series: [
          {
            barWidth: titleFontSize,
            itemStyle: {
              barBorderRadius: [titleFontSize/2, titleFontSize/2,0,0]
            }
          }
        ]
      }
      this.chartInstance.setOption(adapterOption)
      this.chartInstance.resize()
    },
    startInterval() {
      if(this.timeId) {
        clearInterval(this.timeId)
      }

      this.timeId = setInterval(() => {
        this.startValue++;
        this.endValue++;
        if(this.endValue > this.allData.length -1) {
          this.startValue = 0;
          this.endValue = 9;
        }
        this.updateChart()
      }, 2000);
    }
  },
}
</script>
 
<style lang = "less" scoped>
  
</style>